Flare-type pilot burner



March 16, 1965 M, SEVERSON 3,173,471

FLARE-TYPE PILOT BURNER Filed Dec. 4. 1961 1h fft:

Ii Ii lii INVENTOR. ASBJ'ORNM Sz'mzs'ow ATTORNEY United States Patent "ce 3,173,471 FLARE-TYPE PILOT BURNER Asbjorn M. Severson, Minneapolis, Minn, assiguor to Honeywell Inc., a corporation of Delaware Filed Dec. 4, 1961, Ser. No. 156,601 7 Claims. (Cl. 158115) This invention relates to pilot burners for main gas burners of heating installations and, more particularly, to a flare-type pilot burner for use with a manifold valve having a thermocouple energized safety pilot valve and a modulating type of diaphragm valve therein.

It is customary in gas heating installations to have a main burner for supplying the necessary heat for the heating installation and a pilot burner closely associated therewith for igniting the main burner each time there is a call for heat from the main burner. It is also well known in the heating art to provide a modulating type of diaphragm valve for controlling the flow of gas to the main burner to deliver gas to the main burner at a rate which is proportional to the heat demand. In order to provide this modulation of a diaphragm valve, it is desirable to constantly bleed gas from the pressure chamber of the diaphragm valve to a point adjacent the pilot burner flame so as to burn all of the bleed gas and thus prevent any dangerous accumulation of gas in the combustion chamber of the heating installation.

It is one of the objects of this invention to provide a compact combination of a pilot burner and a flare or bleed burner closely associated therewith to provide the necessary burner apparatus for a heating installation, such as the one mentioned above.

Another object of the invention is to provide a compact pilot burner and flare burner arrangement wherein the gas supplied to the pilot burner and flare burner flows to these burners through a common inlet. 1

Another object of the invention is to provide a combination of a pilot burner and a flare burner wherein means is provided to cause substantially all of the gas to flow to the pilot burner when the rate of gas flow to the combination is below a certain level and to continue substantially the same rate of flow of gas to the pilot burner after there has been a substantial increase in the rate of gas flow to the combination but with most of the additional gas flow passing on to the flare burner.

Still another object of the invention is to provide a pilot burner and flare burner combination wherein gas is burned in each of the burners at a gas pressure only slightly above atmospheric pressure.

A still further object of the invention is to provide a pilot burner-flare burner combination wherein the flare burner is in the form of a ring and the pilot burner is in the form of a substantially smaller ring positioned Within the ring of the flare burner.

A still further object of the invention is to provide a combination of an annular flare burner mounted in arcuate grooves in a burner manifold and a smaller annular burner positioned within the flare burner between the flare burner and the manifold and held against the manifold by means of resilient means positioned between the pilot burner and the flare burner.

Other objects of the invention will become apparent upon reading the following detailed description of the invention in conjunction with the accompanying drawing wherein:

FIGURE 1 is a plan view of the invention;

FIGURE 2 is a vertical sectional view of the invention taken along line 22 of FIGURE 1; and

FIGURE 3 is a fragmentary, vertical sectional view of the invention taken along line 3-3 of FIGURE 1.

The flare-type pilot burner unit or assembly includes 3,173,471 Patented Mar. 16, 1965 a manifold 11 having a stepped bore 12 therein extending longitudinally therethrough. The left-hand end of the bore 12 is threaded at 12a and is closed by a threaded plug 13. Substantially at the center of the manifold 11, there is a vertically extending bore or passageway 14 that intersects the bore 12. It is sealed at its upper end by a headed plug 15, that is frictionally or otherwise held therein, While the lower end of the bore 14 is closed by a deflector or diverter in the form of a tubular member 16 also frictionally or otherwise held therein. The upper end of the tubular member 16 is beveled and is so positioned that the upped left-hand end of the beveled portion extends into the bore 12, substantially to the longitudinal axis thereof. The lower end of the tubular member 16 is closed by a disk 16b forced therein. The bore 12 has a reduced diameter portion 12b and a still further reduced diameter portion at the right-hand side of the bore 14, as viewed in FIGURE 2 of the drawing, which receive and position, respectively, a cupshaped orifice or jet member 17, having a gas fiow regulating orifice 17a therein, coaxially within the bore 12. The righthand end of the bore 12 has an enlarged diameter portion 12d that is threaded to receive the end of a threaded conduit 18. The conduit 18 is for connecting the manifold 11 to the outlet of a manifold gas valve of the type wherein said outlet is connected to a pilot burner gas control valve and the pressure chamber of a diaphragm valve.

At the left-hand end of the manifold 11, there is a vertically extending bore or passageway 19 that intersects the bore 12 and terminates a short distance downwardly from the top of the manifold 11. The lower end of the bore 19 is threaded and is closed by a threaded plug 20.

Two longitudinally spaced arcuate grooves 21 and 22 have positioned therein an annular burner generally designed by the reference numeral 23. This burner comprises an annular channel shaped member 24 having a bore in an outer wall thereof that registers with the upper end of the bore 19. A burner head has a cylindrical portion 26, with a reduced diameter portion 27, and an annular outwardly extending flange portion 28 at the top of the portion 27. The outer edge of the flange 28 extends slightly beyond the outer wall of the channel shaped portion 24 and provides an annular slot therebetween. A plurality of arcuate slots 29 are formed in the reduced diameter portion 27 so that as gas issues from the channel shaped member 24, some gas will pass through the arcuate slots and some through the annular slot to provide spaced flames that rise up over the flange portion to join above the flange portion into a single annular flame.

A second much smaller annular burner, generally designated by the reference numeral 30, comprises a small annular channel shaped member 31 which is resiliently held in an arcuate notch 32 formed in the upper edge of the manifold body 11 opposite the bore 14. A bore 33, formed in the outer side wall of the channel shaped member 31, registers with an upwardly inclined bore 34 formed in the side of the manifold body 11 to establish communication between the bore 14 and the interior of the channel shaped member 31. A leaf spring 35 has its two ends resting against the outer surface of the inner wall of the channel shaped member 24, between two arcuate ribs 36 and 37 formed on said surface, with the central portion of the spring bearing against the outer surface of the outer wall of the channel shaped member 31 between arcuate ribs 38 and 39 formed on said surface. It is thus seen that the channel shaped member 31 is snugly held against the surfaces of the notch 32 to provide a gas tight seal between the channel shaped member and the notch surrounding the bore 34. Obviously, if desired, the channel shaped member 31 could be welded or secured to the manifold body 11 by any other suitable means, although the present construction makes it possible to disassemble the elements, if so desired. The small burner has a cylindrical portion 40 that has an inside diameter equal to the large diameter of the inner wall of the channel shaped member 31 around which it fits andhas an outwardly extending flange portion 41 that extends slightly over the outer wall of the channel shaped member 31 to provide an annular groove therebetween. The upper end of the Wall 41 has a plurality of arcuate slots 42 therein similar to and for the same purpose as the slots 2 in the large burner 23. When gas is supplied to the channel shaped member 31, gas will rise and pass through the slots 42 and the annular outer groove to produce two flames which join above the flange 41 to produce a single annular flame.

The two burners 40 and 23 are sufficiently close together that the gas issuing from the larger burner 23 Will be ignited by the flame from the burner 40. Also, if by some chance the flame burner 40 should become extinguished while a flame is present at the burner 23, the gas from the burner 40 wouldbe reignited by the flame from burner 23.

Operation With the above described burner unit mounted in a heating system with the burner so arranged that a main burner of the heating system is able to be ignited by the flame from the burner 23, and with the conduit 18 connected to a manifold valve having a combined pilot burner and bleed control gas outlet, the system is placed into operation by supplying gas to the manifold body 11 through the conduit 18 from the pilot gas control valve in the manifold valve. Under these conditions, gas will flow through the orifice member 17 and into the bore 14. Due to the fact that there is a very slow rate of gas flow at this time, the gas will tend to rise by convection upwardly through the bore 14, through the inclined bore 34, through the bore 33 and out through the arcuate slots 42 and annular slot in the pilot burner 30 where it will be ignited by some suitable means. It is believed that any tendency for the gas issuing from the orifice 17a of the orifice member 17 to pass beyond the bore 14 into the bore 12 and bore 19 is substantially prevented by the deflector 1-6 that tends to create turbulence at the inlet to the bore 12 opposite the orifice member so as to effectively block gas flow except upwardly through the bore 14.

The burner 30 is adapted to heat a thermocouple (not shown) positioned coaxially within the burner 39 in a conventional way so that when the thermocouple is sufficiently energized, a safety valve in the manifold valve for controlling the main gas flow to the main burner is held open and gas is free to flow to the main burner through a diaphragm controlled valve which, in turn, is thermostatically or manually controlled in a conventional manner by a diaphragm controller valve.

Upon a call for heat by the heating system, in response to the closing of a room thermostat for example, the diaphragm controller valve is actuated to cause bleed gas to flow through the conduit 18 into the manifold 11. With this substantial increase in gas flow, the gas entering the bore 14 will be forced past the diverter member 16 and flow to the large annular burner 23 where it will be ignited by the burner 30. This will take place without any substantial increase in the size of the flame heating the thermocouple, as substantially all of the extra gas flows to the larger burner 23. The increased gas velocity through orifice 17 establishes a gas flow or stream into the bore 12. The effect of the increased gas flow is to reduce the pressure surrounding the jet stream in tube 14. Without the deflector 16 a partial vacuum is generated in bore 14 and no gas issues from burner 39. Deflector 16 causes sufficient interrercnce with the cross stream flow to peel off enough gas to overcome the ejector effect and maintain essentially a constant flow from burner 30. The gas that flows to the main burner is then ignited by the flame from the burner 23. When the diaphragm controller valve closes, the flame from burner 23 will extinguish leaving only the gas from burner 30 still burning.

While I have described the preferred embodiment of my invention above, it is obvious that modifications may be made thereof without departing from the spirit of the invention. The scope of the invention should therefore be determined from the appended claims.

I claim:

1. A flare-type pilot burner unit comprising a manifold having an inlet, a first outlet connected to said inlet, a second outlet connected to said inlet, an orifice member in said inlet arranged to direct fuel toward the center of said second outlet, a first burner having an inlet in communication with said first outlet, deflector means positioned at said second outlet and projecting from the opposite side thereof from said first burner to a point only so far across said second outlet as to cause substantially all of the fuel to flow toward said first burner at low fuel flow rates but to allow substantially all of the additional fuel to flow past said deflector means at higher fuel flow rates, and a second larger burner near said first burner for ignition thereby and having an inlet in communication with said second outlet.

2. A flare-type pilot burner unit comprising a manifold having a horizontally extending bore therein open at one end to provide an inlet thereto and closed at the other end, a first outlet passageway intersecting said horizontally extending bore and dividing it into an inlet bore and an outlet bore, a second outlet passageway intersecting said outlet bore, a first burner at the outer end of said first outlet passageway, deflector means positioned at said outlet bore and projecting from the lower side of said outlet bore to a point less than halfway across said outlet bore so as to cause substantially all of a jet of fuel from said inlet bore to flow toward said first burner at low fuel flow rates but to allow substantially all of the additional fuel to flow past said deflector means at higher fuel flow rates, and a second larger burner near said first burner for ignition thereby and in communication with said second outlet bore.

3. A flare-type pilot burner unit as defined in claim 2, wherein said first outlet passageway lies between the open end of said horizontally extending bore and said second outlet passageway.

4. The combination comprising a gas manifold having an open end and a closed end, a first outlet from said manifold at a point intermediate its ends, an orifice member in said manifold between said first outlet and said open end, a second outlet from said manifold near its closed end, a first burner mounted on said manifold and having an inlet in communication with said first outlet, defiector means positioned in said manifold at said first outlet and projecting from a lower portion of said manifold upwardly toward said first outlet only so far across the entrance to said second outlet as to cause substantially all of the fuel to flow toward said first burner at low gas flow rates but to allow substantially all of the additional gas to flow past said deflector means at higher gas flow rates, and a second larger burner mounted on said manifold near said first burner for ignition thereby and having an inlet in communication with said second outlet.

5. The combination of claim 4 wherein said first burner is of annular shape and said second burner is of much larger annular shape and surrounding said first burner.

6. The combination of claim 4 wherein said first burner is held in assembled relationship against said manifold by means of resilient means positioned between said burners to provide sealing contact between the first burner and said manifold around the first outlet and the inlet to said first burner.

5 7. A flare-type pilot burner unit comprising a manifold having a longitudinal bore with an open end and a closed end, a first outlet passageway intersecting said longitudinal bore intermediate its ends and dividing it into an inlet bore and an outlet bore, a second outlet passageway communicating with said outlet bore, an orifice member in said inlet bore and positioned to direct fuel toward the center of said outlet bore, a first burner mounted on said manifold and having an inlet in communication with said first outlet passageway, deflector means positioned at the opposite side of said outlet bore from said first burner and projecting partially across said outlet bore so as to cause substantially all of the fuel to flow toward said first burner at low fuel flow rates but to allow substantially all of the additional fuel to flow past said deflector means at higher fuel flow rates, and a second larger burner mounted on said manifold near said first burner for ignition thereby and having an inlet in communication with said second outlet passageway.

f (3 References Cited by the Examiner UNITED STATES PATENTS 2/93 Clayton 158-105 9/13 Mott 158-115 X 7/15 Eddy 158-115 X 6/29 Calvert 158-114 X 10/31 Epstein 158115 5/32 Carlsen 1S8-115 4/33 Holstein 28753 7/51 Harrison 158-117 X 12/53 Swenson et a1 158-115 X FOREIGN PATENTS 10/60 France.

JAMES \V. WESTHAVER, Primary Examiner.

FREDERICK L. MATTESON, IR., Examiner, 

1. A FLARE-TYPE PILOT BURNER UNIT COMPRISING A MANIFOLD HAVING AN INLET, A FIRST OUTLET CONNECTED TO SAID INLET, A SECOND OUTLET CONNECTED TO SAID INLET, AN ORIFICE MEMBER IN SAID INLET ARRANGED TO DIRECT FUEL TOWARD THE CENTER OF SAID SECOND OUTLET, A FIRST BURNER HAVING AN INLET IN COMMUNICATION WITH SAID FIRST OUTLET, DEFLECTOR MEANS POSITIONED AT SAID SECOND OUTLET AND PROJECTING FROM THE OPPOSITE SIDE THEREOF FROM SAID BURNER TO A POINT ONLY SO FAR ACROSS SAID SECOND OUTLET AS TO CAUSE SUBSTANTIALLY ALL OF THE FUEL TO FLOW TOWARD SAID FIRST BURNER AT LOW FUEL FLOW RATES BUT TO ALLOW SUBSTANTIALLY ALL OF THE ADDITIONAL FUEL TO FLOW PAST SAID DEFLECTOR MEANS AT HIGHER FUEL FLOW RATES, AND A SECOND LARGER BURNER NEAR SAID FIRST BURNER FOR IGNITION THEREBY AND HAVING AN INLET IN COMMUNICATION WITH SAID SECOND OUTLET. 